Re: ScanTesla program

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jim Lux" <jimlux@xxxxxxxxxxxxx>


----- Original Message -----
From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Saturday, May 14, 2005 10:46 AM
Subject: Re: ScanTesla program


> Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>
>
> Hi Steve,
>
> >I've already done the 3-d plots by hand :P I used the parametric
> >simulation feature to do blocks of 10 simulations varying one parameter,
> >and did 10 of those blocks, then typed the 100 results into Excel for 3-d
> >plotting. The parameters I investigated were streamer resistance and
> >capacitance and the dependent variable was peak primary current.
> >http://forum.4hv.org/attachments/loadingmap.gif
>
> Yes!!  That is the type of stuff the program should do!  Like you, I just
> don't want to sit there working for hours running models and typing in
> numbers.  The new program should make it all automatic.  Of course, it can
> do many parameters are run a very large number of models that we could
> never do by hand.
>
> Antonio Wrote:
>
> >Could be something similar to the programs Optesla and Optmag, that I
> >wrote to search the design space for capacitor-discharge Tesla coils
> >and magnifiers (http://www.coe.ufrj.br/~acmq/programs). I didn't add
> >a load in your style, but this would not be difficult.
> >I have a DRSSTC simulator in the program Sstcd. Almost your structure.
> >In that case I didn't use an exact solution, but this would not be
> >very difficult to implement.
>
> Jim Wrote:
>
> >1) Do this as a matrix equation as in classical network analysis (like
> >Spice, MicroSim, etc.) use.  You build up an matrix representing all the
> >interconnections and admittances, then solve it.
>
> Very close to the same thing as Antonio's program but more designed to
scan
> a large number of parameters.  Right now I really don't want to find
closed
> form solutions since the program may evolve in ways that make that very
> difficult.  If the loads start to get time dependent like in Steve's model
> or other changes are made (output feedback), fixed solutions equations my
> be difficult to change or intractable.

Matlab wouldn't find closed form solutions.  You build the matrix up from
the component values, then solve it for the voltages and currents (which is
what SPICE does for the "steady state" AC solutions).  Nothing keeping you
from changing the matrix as a function of time.


  The P-spice style number crunching
> is orders of magnitude slower but it can handle any situation with
> relatively minor changes.  Eventually, it may be obvious that things don't
> change much and it would be best to solve the equations to take advantage
> of the higher speed.  At that point, the "answers" might be directly
> calculable anyway.  Also, the matrix math is a little more than "I" want
to
> chew on 0:-)

I, too, thought that.  But once you've got a half dozen or so components in
the circuit, it gets easier to write a simple routine to crank up the
admittance matrix (you write a "connect component between node x and node y"
routine, so your circuit design is just a series of calls to that routine).
Especially if you make the routine something like:

addcomponent (complex impedance, node 1, node 2)

and then do

Ymatrix = zeroes(20);        % makes a 20x20 matrix of zeros
addcomponent (resistance, a, b,Ymatrix)
or
addcomponent (1/(1j * omega * capacitance), a, b, Ymatrix)

etc
etc


>
> I don't want the program to be tied to Excel or Matlab since it should be
a
> total freebie that anyone can run.

Octave is a Matlab clone, and free.  It might not have all the exotic
toolboxes for Matlab, but it will certainly do all the complex matrix math.

 It may not be the optimal or best way
> to do things, but it should be a good place to start out.  Those program
> are nice in that one can fiddle with things easily.  But LCC is almost
> interpreted language like these days so fiddling is pretty easy even in
> C.  I "think" you can even import C type programs into Excel and Matlab as
> sort of a "function engine", but all that is far beyond me and my use.
>